Struct PerCoreWalManager 

pub struct PerCoreWalManager { /* private fields */ }

Per-core WAL manager.

Coordinates all core WAL writers and provides epoch management. Each core has its own writer, eliminating cross-core synchronization on writes.

Implementations

impl PerCoreWalManager

pub fn new(config: PerCoreWalConfig) -> Result<Self, PerCoreWalError>

Creates a new per-core WAL manager.

Creates segment files for all cores if they don’t exist.

Errors

Returns an error if directory creation or writer initialization fails.

pub fn open(config: PerCoreWalConfig) -> Result<Self, PerCoreWalError>

Opens an existing per-core WAL manager.

All segment files must exist.

Errors

Returns an error if any segment file doesn’t exist or can’t be opened.

pub fn config(&self) -> &PerCoreWalConfig

Returns the configuration.

pub fn num_cores(&self) -> usize

Returns the number of cores.

pub fn epoch(&self) -> u64

Returns the current global epoch.

pub fn epoch_ref(&self) -> Arc<AtomicU64>

Returns a shared reference to the global epoch counter.

pub fn writer(&mut self, core_id: usize) -> &mut CoreWalWriter

Gets the writer for a specific core.

Panics

Panics if core_id >= num_cores.

pub fn writer_checked( &mut self, core_id: usize, ) -> Result<&mut CoreWalWriter, PerCoreWalError>

Gets the writer for a specific core, checking bounds.

Errors

Returns an error if core_id >= num_cores.

pub fn advance_epoch(&self) -> u64

Advances the global epoch and returns the new epoch.

pub fn set_epoch_all(&mut self, epoch: u64)

Sets the epoch on all writers.

pub fn sync_all(&mut self) -> Result<(), PerCoreWalError>

Syncs all segment files.

Errors

Returns an error if any sync fails.

pub fn positions(&self) -> Vec<u64>

Returns the current write positions of all writers (includes un-synced data).

For checkpoint manifests, prefer synced_positions() which only reports durable data.

pub fn synced_positions(&self) -> Vec<u64>

Returns the last synced (durable) positions of all writers.

Only data up to these positions is guaranteed to survive a crash. Use this for checkpoint manifests.

pub fn truncate_all(&mut self, positions: &[u64]) -> Result<(), PerCoreWalError>

Truncates all segments at the specified positions.

Errors

Returns an error if any truncation fails.

pub fn reset_all(&mut self) -> Result<(), PerCoreWalError>

Resets (truncates to zero) all segments.

Used after successful checkpoint.

Errors

Returns an error if any reset fails.

pub fn merge_segments(&self) -> Result<Vec<PerCoreWalEntry>, PerCoreWalError>

Merges entries from all segments, sorted by (epoch, timestamp).

Errors

Returns an error if reading any segment fails.

pub fn merge_segments_up_to_epoch( &self, max_epoch: u64, ) -> Result<Vec<PerCoreWalEntry>, PerCoreWalError>

Merges entries from all segments up to a specific epoch.

Errors

Returns an error if reading any segment fails.

pub fn write_epoch_barrier_all(&mut self) -> Result<(), PerCoreWalError>

Writes an epoch barrier to all segments.

Used during checkpoint to mark epoch boundaries.

Errors

Returns an error if any write fails.

pub fn check_all_completions( &mut self, completions: &[IoCompletion], ) -> Result<usize, PerCoreWalError>

Check I/O completions against all writers’ pending sync tokens.

Call this after polling StorageIo::poll_completions. Each writer that has a pending sync token matching a completion will update its synced_position.

Returns the number of writers whose syncs completed successfully.

Errors

Returns the first PerCoreWalError encountered if any writer’s sync failed.

pub fn any_sync_pending(&self) -> bool

Returns true if any writer has a pending sync.

pub fn total_size(&self) -> u64

Returns total size of all segments.

pub fn segment_path(&self, core_id: usize) -> PathBuf

Returns segment path for a core.

Trait Implementations

impl Debug for PerCoreWalManager

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.